Apparatus for molding concrete t-beams



June 11, 1963 E. GQM. DYKEMAN ETAL 3,092,886

APPARATUS FOR MOLDING CONCRETE T-BEAMS Filed May 1l, 1959 3 Sheets-Sheet 1 IOO 'A F'IE E INVENTORS EDGAR G. M. DYKEMAN JOHN N. KELLEY ATTQRNEY June 11, 1963 E. G. M. DYKEMAN ETAL 3,092,886

APPARATUS FOR MoLDING CONCRETE T-BEAMs 3 Sheets-Sheet 2 Filed May 11, 1959 F'IE :EI

IF I E l- INVENTORS I IE.- EDGAR G. M. DYKEMAN JOHN N. KELLEY BVM ATTORNEY 3 Sheets-Sheet 3 INVENTORS EDGAR G. M. DYKEMAN JOHN N. KELLEY E. G. M. DYKEMAN ETAL `lune 1l, 1963 APPARATUS FOR MOLDING CONCRETE T-BEAMS Filed May 11, 1959 BY /ULfW'VWLV- ATTORNEY United States Patent O 3,092,886 APPARATUS FOR MOLDING CONCRETE T-BEAMS Edgar G. M. Dykeman, Riverside, and lohn Kelley,

Arlington, Calif., assigner-s to FMC Corporation, a corporation of Delaware Filed May 11, 1959, Ser. No. 824,446 6 Claims. (Cl. 25-121) This invention relates to concrete structural members and in particular pertains to apparatus for molding concrete beams of T-shaped cross-section.

T-beam molding apparatus presently in use is cumbersome and expensive and does not provide ilexibility in the number or in the dimensions of the beams that can be molded therein. Costly auxiliary equipment such as cable tensioning devices are tied up with each new beam until the concrete has hardened and this further adds to the costs. Leakage of the concrete being molded in presently used apparatus is also frequently a factor that contributes to the cost of using such apparatus, particularly when vibration is resorted to to eliminate voids in the concrete.

Another object is to provide an improved apparatus for molding concrete beams.

Another object of the invention is to provide molding apparatus which is adjustable to permit variation of the dimensions thereof so that beams of various sizes can be cast therein.

Another object of the invention is to provide beam forming apparatus including side molding members which can easily and quickly be tilted into a spread apart relationship to facilitate removal of a cast beam from the mold, and which can easily and quickly be returned to their position for use in pouring another beam.

Another object of the invention is lto provide concrete molding apparatus which is not subject to excessive concrete leakage.

Another object of the invention is to provide improved concrete forming apparatus which permits unobstructed nishing of the top surface of a beam being formed therein.

Another object of the invention is to provide improved apparatus for molding a plurality of concrete beams.

These and other objects and advantages of the invention will be apparent from the following description taken in connection with the drawings, in which:

FIG. 1 is a perspective of one section of the molding apparatus Viewed from one end thereof and illustrates a finished concrete T-beam therein.

FIG. 2 is .a plan of the mold section of FIG. 1, drawn to a reduced scale.

FIG. 3 is a side elevation of the mold section of FIG. 2.

FIG. 4 is an enlarged end elevation of the mold section of FIGS. 2 and 3.

FIGS. 5 and 6 are side elevations on an enlarged scale of a toggle device for a mold side member support.

lFIG. 7 is a plan on a reduced scale illustrating the molding apparatus of the invention adapted for simultaneous production of a number of concrete T-beams.

A horizontal concrete casting bed 8 (FIGS. 1 and 7) supports the molding apparatus 16 of the invention and the beam or beams being cast therein. As clearly shown in FIG. 7 the molding apparatus comprises a plurality of sections 12 disposed in end-to-end arrangement. Each section 12 includes a pair of side forming members 14 (FIGS. 1-4) which tilt into and out of molding posi-V tion under the control of toggled supports 16 (FIGS. l and 3-6). The bottom of the mold is closed by a member 18 (FIGS. 1, 2 and 4) which serves as a pallet for the iinished beam. The member 18 is positioned between the side forming members 14 and is tightly engaged thereby when they are tilted into molding position. The ends "ice of the connected sections 12 are closed at their outer ends by end plates 19 (FIG. 7), thus completing an open topped elongate molding cavity for receiving green concrete. Stressing members such as cables 2Q (FIGS. 1 and 7) may be placed in the cavity of the form if prestressed beams are to be cast. The dimensions of the mold section 12 can be varied so that beams 22 (FIG. l) of various sizes can be produced therein; and since a plurality of the sections 12 are in end-to-end relation, the apparatus is adapted for the production of several beams 22, 22a and 22h (FIGS. l and 7) concurrently in the elongate molding cavity. The elongate cavity can be partitioned at intervals to provide several individual beam molding cavities 23 of desired length. The beam stressing cables Ztl (FIGS. 1 and 7) extend the entire length of the elongate molding cavity and are common to all of the beams being cast at one time in the several individual molding cavities 23. The cables are anchored at one end of the molding apparatus 19 and are all tensioned by a single tensioning device located at the other end of the apparatus 1t).

Each molding section 12 (FIGS. 1-4) of the apparatus 10 is supported on the concrete casting bed 3 (FIG. 1) as above stated. The side forming members 14 which comprise the section 12 are of identical construction and therefore only one will be described. They face each other and are separated sufficiently to accommodate the support member or pallet 1S between them. Each of the side molding members 14 is constructed of a steel sheet 24 (FIG. 2) bent longitudinally to provide a vertical wall 2S (see FIGS. l and 3), a narrow oblique wall 30 and a substantially horizontal wall 32. The slab of a beam 22 may be made to taper toward the outer edges thereof by slightly inclining the walls 32 upward and outward.

Triangular reinforcing plates 34 (FIGS. 1, 3 and 4) are.

welded to the walls 23, 30 and 32 of each side molding member at suitable intervals throughout the length of the mold section 12. Welded to the outer edge of the wall 32 and to the outer ends of the reinforcing plates 34 is a stiening plate 36 (FIGS. 1, 3 and 4), which extends the full length of the molding member 14. At each end of the plate 36 (FIGS. 3 and 4) is welded an inverted U-shaped bracket 38 whereby one of the mentioned toggled supports 16 is connected to the side member 14. Each bracket 38 is drilled to accommodate a pivot pin 4t). The toggled support 16 includes a support strut 42 whose upper end tits within the sides of the associated U-shaped bracket 38 and is pivoted on the associated pin 40. The lower end `of the support strut 42 is connected to `a transversely extending channel bar 46 by a toggle-joint or knuckle 44 the details of which will be described later herein. One of the channel bars `46 is located under each end of the side molding member 14, and an intermediate channel bar 43 is disposed midway between the two end channel bars `46. All of the channel bars rest upon the casting bed 8. Two slots 5t) are cut in each of the channel bars 46 and 48. A guide bolt 52 extends through each slot Si) into the casting bed '8. The guide bolts are threaded and engage threaded nuts or other threaded devices (not shown) embedded in the concrete of the casting bed 8.

A pair of opposed angle members 54 (FIGS. 1 and 4) are welded to each channel bar 46, 48 adjacent the inner end thereof. The upstanding legs of the angle members 54 of each pair are separated to loosely receive a vertical plate 56 between them. A support bolt 58 extends through the upstanding legs of the angle members 54 of each pair and loosely through the associated vertical plate 56. A horizontally projecting plate 69, integral with the vertical plate 56, is welded to the underside of a stiifening plate 62 which extends the full length of the side molding member 14 and is welded to the lower extremity of the vertical wall 28 and to the several triangular reinforcing plates 34. Since each of the vertical plates 56 rests upon the associated support bolt S, the side molding member 14 is therefore pivotally supported on the casting bed 8 by the three bolts 5S.

VSeparation of the sideV molding members 14 of each section 12 is adjusted by sliding the supporting channel bars y46 and 4S past the guide bolts 52.

Each mold section 12 is opened by tilting back the two side forming members 14 thereof. This releases the walls 2S, 3% and 32 from the undersides of a beam 22 and thus releases the beam for ready removal. Operation of the toggle-joints 44 of the four toggled supports 16 of the mold section 12 causes each of the toggled supports 16 to assume either an erect position, as shown in full lines in FIG.' 4, or alternatively, an outwardly tilted position as shown in broken lines in PEG. 4. In the full-line position of the toggled supports 16, the side members 14 are erect and tightly engage the lateral edges of the pallet 18. In the broken-line tilted position of the toggled supports, the side members 14 are tilted apart, pivoting slightly on the support bolts 5S to the extent permitted by the support struts 42. In their outwardly-tilted positions-no portion of the side forming members 14 contacts the hardened beam 22.

Each toggle-joint 44 (FIGS. 4-6) comprises a pairy of parallel short links `66 which are pivotally connected to the lower end of the associated support strut 42 by a pivot pin 63. II'he links 66 are also pivotally connected to the associated channel bar 46 by a pivot pin 70. A U-shaped bracket 72 is welded to the upper ends of the links 66 above the pivot pin 63.

A short rod 74 is welded to the U-shaped bracket 72 and provides a convenient handle for operating the togglejoint. The toggle-joint 44 has two stable positions-the erect position (PEG. 5) and the tilted position (FIG. 6). In the open position of the mold section 12 the links 66 and the rod 74 of each toggled support 16 have been tilted outward to the extent permitted by the lower end face 76 of the associated support strut 42 abutting against the upper face 78 of the respective channel bar 46. In said open position the weight of the side molding members 14 is directly transmitted to the casting lbed 8 through the abutting faces 76 and 78 of lthe several toggled supports 16. To move the side forming members 14 to erect position, the handles 74 are swung inward to the position shown in FIG. 5. The pivot pins 68 in this manner move past the position of vertical alignment with the pins 7@ and the toggle-joint can be said to snapover-center. Such movement of the toggle-joint therefore continues slightly past the position of vertical alignment of the pivot pins and is limited by the inner face Sil of the support strut 42 striking a stop member 82 bolted or otherwise secured to the associated channel bar 46.

When the toggle-joints 44 of a side molding member 14 are snapped-over-center to place the member 14 in its erect position the toggle joints are so securely locked in their inner positions that they will not accidentally tilt outward. The weight of the concrete and the weight of the member itself urge the strut faces 8l) into tight con- Y tact with the stop members S2 and thus aid in maintaining the mold section in its closed or erect position.

The pivotal axis of each side molding member 14 is located a substantial distance below the plane of the beam supporting pallet. Therefore, when the mold is closed, a considerable force is exerted against the edges of the pallet 118 by the tilted together walls 2S of the side molding members 14. A tightly sealed joint is Ithus established between the Walls 23 and the pallet 1S to prevent concrete leakage.

It will be noted that the side molding members 14 can easily and quickly be tilted together or -tilted apart manually, by use of a simple tool such as a pipe 84 (FIG. 6) which ts over the handle 74 as an extension thereof. Little time or effort is required to use the apparatus because after tilting the members 14 together, nothing except attachment of end plates 19 is required before concrete can be poured into the forming cavity 23.

The present apparatus is adjustable for the production of beams meeting a wide range of design requirements. The thickness of the web of the T-beam to be cast is determined by the width of a horizontal board 93 forming the top of the pallet 18, since the vertical walls 28 of the two side molding members 14 press tightly against the lateral edges of the board 93.. Selection of a board'93 whose width corresponds to the desired web thickness and corresponding adjustment of the side molding members 14 on bolts 52 are all that is necessaryl to adjust the mold section 12 for a selected web thickness.

The depth of the web is determined by the height of the board 93 above the casting bed 8. This height is adjusted by changing the timber 94 which support the board 93 above the casting bed 8. j

The width of the slab 92 of the T-beam to be cast is controlled by two laterally adjustable guide members (FIGS. 1, 2 and 4) which rest on the horizontal walls 32 and extend the full length of the side molding members 14. Each guide member 10i) is constructed of a channel 102 having transverse slots 104 therein. Slots 106 cut in the wall 32 are aligned with corresponding slots 164 and a bolt 108 in each aligned pair of slots 194 and 106 permits the guide member to be slid in and out on the respective horizontal wall 32. The channel 102 is fastened to the wall 32 in selected position of lateral adjustment by tightening the bolts 108. A facing member 110, welded to each channel, bevels the lower edge of the slab 92 of `the T-beam.

The slab thickness of the beam to be cast isdeterminedV by screeding strips 116, one of which is mounted upon each vof the channels 162 with the inner face of the strip 116 in alignment ywith the inner face of the associated facing member 11G, as best shown in FIG. 4. Between each screeding strip I116 and the associated channel 162 is a spacing yblock 112, #and consequently all that isl neessary to prepare the mold sections, as far as web thickness is concerned, is to select spacing blocks 112 of such a thickness that they support their respective screeding strips 116 with the-upper faces of the latter at the vertical distance above the upper faces of the horizontal wall 32 which corresponds to the desired'thickness of the Islab edge. Bolts 114 extending through the screeding strips 116, spacing blocks 112 and channels 102 rigidly retain these parts in their desired relationship. The bolts 114 are shown extended through and above the screeding strip 116 to receive nuts 117. However, the t-op sur-faces :of the |screeding strips 116 could be left'unencumbered, thus to facilitate the operations vof leveling `and finishing the upper surfaces of freshly poured beams, by Welding the head-s of the bolts 114 to the undcrsurfaces of the respective screeding strip 116 so that the shanks of the bolts would extend therefrom downward through therespective spacing .block 112 and channel y162 to receive nuts that could be tightened upward against the undersurfaces of the webs of the channels 102.

The length of the T-zbeam is the other dimension requiring adjustment `and this is provided for by connecting a plurality of sections 12 of the apparatus together. Holes 1211 (FIG. 4) are drilled at appropriate points in the two triangular reinforcing plates 34 at the ends'rof each section 12. This permits two adjacent sections to be joined by bolts placed through the aligned holes 120. In this fashion an elongate molding cavity could be provided having -a length only slightly less than the length of the casting bed 8.

FIGUR-E 7 illustrates -four sections 12 bolted together in the manner ydescribed and connected to the casting bed i8 by the guide bolts 52 (FIG. l). The elongate molding cavi-ty thus created lis partitioned into individual beam molding cavities :by locating headers 132, 133, i134 and 135 selected distances `apart in the elongate cavity. The headers are fabricated of plywood or other material and are cut to conform to the cross sectional shape of the molding cavity. The headers therefore engage and seal against the tilted together side molding members 14 just `as the pallet liner seals against the members 14. The headers also contain appropriate holes for receiving beam stressing members such as the steel cables 20 which are connected to a tensioning machine 124 (FIG. 7) at one end of the elongate cavity 23 and to a suitable anchor 126 at the other end of the cavity. inasmuch as the details of construction and manner of `operation of the tensioning machine 124 and of the anchor 126 do not form part of the present invention, they need not be described in detail herein. A possible pattern for laying the cables 26 is shown by the end of the beam 22 illustrated in FIG. l. The cables 20 are threaded through appropriate holes in the hereinabove mentioned end plates 19, one of which is attached to each end of the `apparatus and through the holes in the headers .132, 133, 134 and 135. On the other hand, the cables 20 can be threaded .through the end plates and the headers as a preliminary step. This permits the end plates and headers to be inserted into the mold cavity with the cables threaded therethrough, after which the cables can be attached to the tensioning apparatus land the cable anchor. With some cable patterns the headers and end plates may be provided with slots rather than holes for receiving the cables.

A pair of the headers spaced a short distance apart are placed in the elongate molding cavity to define the limits of the adjacent individual beam molding cavities. Each pair of adjacent headers (132 and 133) is termed a header member 140 (FIG. 7). The separation of headers 132 and 133 `of a header member is approximately one foot and the separation of headers 133 and 134 determines the length of the beam 22a. The separation of the header 132 and the end plate 19 determines the length of the beam 22h.

The headers of a header member 140 must be supported against the pressure exerted `by the fluid concrete placed in the individual beam molding cavity. Such support can be provided by attaching a clamp 142 to each of the several steel cables 20 where the cables emerge from the headers. Spacers of Wood or other material could lalso be used to support the headers of a header member against the concrete pressure. C-clamps or other devices may be used on top of the headers to hold the headers down in the cavity but this is usually not necessary. Sealing of the holes Where the cables pass through the headers can be yachieved by devices such as common O-rings, but this too is usually not necessary.

After the header members 140 are installed and the end plates 19 attached, the cables are ystressed to the desired degree by the tensioning machine 124. Concrete is then poured into the individual molding cavities and if necessary subjected to mechanical vibration to eliminate voids. No concrete has been poured in the right-hand beam cavity Z3 of FIG. 7 and the cables 2U are exposed therein. After vibration suitable screeding and finishing operations are performed lat the top surface of the beam. It is to be noted that no cross-ties are necessary with the present apparatus, there are therefore, no bracing bars or other members extending across the top of the form to interfere with the linishing of the beam. When a suiicierit time has elapsed to permit the concrete to attain suflicient strength the tensioning machine is released. This relaxes the short pieces of cable connecting the adjacent beams. The spacers or clamps 142 are then removed and the two headers of each header member 140 are moved away from the vertical end faces of the beams. The end plates 19 are also removed. This exposes the cables at the points where they emerge from the concrete and permits the cables to be `cut off flush with the end faces of the beams. Suitable lengths of cable could be left projecting yfrom the beam ends if it is desired. The toggle-joints 44 `are then released and the mold sections 14 swing outward. This opens the molding apparatus so that the individual beams can readily be removed by a crane or otherwise. Suitable lifting hooks 148 (FIG. 7) can be cast in the beams for this purpose. The toggle-joints 44 can be opened at any time after the concrete hardens; this is a matter of choice because the beam is supported above the casting bed 8 when the side molding members 14 are tiltedapart by the timber 94 and the board 93 of the pallet 18 (FIGS. l and 4).

While one form of apparatus for carrying out the present invention has been described, it should be noted that various modica-tions may be made without departing from the spirit of the invention as defined by the appended claims.

The invention having thus been described, what is believed to be new and desired to be protected by Letters Patent is:

1. For use in molding apparatus for a concrete beam having a horizontal at slab section and a vertical web section, an article of manufacture comprising a pivotally mounted molding member having a first forming surface for forming a side of said web section and a second forming surface extending laterally from said first forming surface for forming an adjacent underside of said slab section, means on said second forming surface to receive a forming member for the lateral side of said slab section, a rigid strut pivotally connected at one of its ends to said molding member beneath said slab forming surface, a link having a pivotal connection at one of its ends with the other end of said strut to form a movable toggle joint. support means, means securing the other end of said link to said support means so that said strut and said link are movable into and out of coaxial alignment, means pivotally mounting the molding member on said support means for movement of said first forming surface, means mounted on said support means in spaced relation to said other end of said link for limiting the movement of said toggle joint in one direction at a position whereby said strut and said link are out of coaxial alignment to cause the weight of concrete on said slab forming surface to lock said strut and link in place, and means for moving said toggle joint in a second direction to cause said molding member to pivot and be released from a concrete beam formed thereon.

2. For use in molding apparatus for a concrete T- beam having a horizontal fiat slab section and a vertical web section, an article of manu-facture comprising a molding member having a first forming surface for forming a side of said web section yand a second forming surface extending laterally from said first forming surface for forming an adjacent underside of said slab section, means on said second forming surface to receive a forming member for the lateral side of said slab section, a rigid strut pivotally connected at one of its ends to said molding member beneath said slab forming surface, a link having a pivotal connection with the other end of said strut to form a toggle joint, support means for pivotally mounting said link and the web forming portion of said molding member at spaced locations on said support means Whereby said toggle joint is movable toward and away from said web forming surface to cause said strut and said link to move into and out of coaxial alignment, stop means mounted on said support means in spaced relation to said other end of said link for limiting movement of said toggle joint toward said web forming surface at a position whereby said strut and said link are slightly out of coaxial alignment to cause the weight of concrete on said slab forming surface to lock said strut and link in place, and means for moving said toggle joint away from said web forming surface to cause said molding member to pivot and be released from a concrete T-beam formed thereon.

3. In molding apparatus for a concrete T-beam having a horizontal at slab section and a vertical web section, said apparatus including means for forming the ends of the beam and means for for-ming the sides of said slab section; the combination comprising a web bottom forming member, a pair of opposed spaced molding members with said web bottom forming member therebetween and having forming surfaces for forming the sides of said web and the adjacent undersides of said slab, a pair of rigid struts each being pivotally connected at one of its ends to one of said molding members beneath the associated slab forming surface, a pair of links each having a pivotal connection at one of its ends with one of said struts at the other end thereof to form a toggle joint, means anchoring the other ends of each of said links to support means so that each of said toggle joints are movable toward and away from said web bottom forming member to move the associated link and strut into and out of coaxial alignment, means for pivotally mounting said web side forming portions of said molding members on said support means and below the forming surface of said webbottom forming member, means mounted on said support means in spaced relation to said other endsrof said links for limiting movement of each said toggle joint in one direction at a position whereby its strut and link are out of coaxial alignment to cause the weight of concrete on the associated slab forming sur-face to lock said strut and link in place, and means for moving each toggle joint in the opposite direction to cause the associated mold-ing member to release the concrete T-beam formed thereby.

4. In molding apparatus for a concrete T-beam having a horizontal ilat slab section and a vertical web section, said apparatus including means for forming the ends of said beam and means for forming the side portions of said slab portions of said slab section and a web bottom forming member; the` improvement comprising a pair of opposed spaced molding members with said web bottom forming member therebetween and having forming surfaces for forming the sides of said web section and the adjacent undersides of said slab section, a pair of rigid struts each being pivotally connected at one of its ends to one of said molding members beneath the associated slab forming surfaces, a pair of links each having a pivotal connection with one of saidstruts at the other end thereof to form a toggle joint, each toggle joint being movable toward and away from said web bottom forming member Yto move the associated link and strut into and out of coaxial alignment, support means pivotally mounting said molding members and said links in spaced apart relation- Vship and at an Velevation below the forming surface of said web bottom forming member, stop means mounted on said support means in spaced-relation to said other. end of said links, means for limiting movement of each of said toggle joints toward said web bottom forming member at a position where-in the associated strut and link are slightly out of coaxial alignment to cause the weight of concrete on the associated slab forming surface to lock said strut and link in place and rigid means connected to said link-s and extending in a direction away from said support means for moving the toggle joints away from said web bottom forming member to cause said molding member to pivot apart and release the concrete T-beam formed therebetween.

5. Apparatus `for molding a concrete T-beam having a horizontal at slab section and a vertical web section cornprising a iirst molding member and a second molding mem- Iber, each molding member having a wall for Amolding a respective side of said web section, the -Wall of one molding member extending in a vertical plane parallel to the plane in which the wall of the other molding member extends, each molding member having a wall for molding the adjacent underside of said slab section, said lastnamed wall including means for molding the associated lateral edge of the slab, means alixed to the transverse ends of each molding member and extending across the space between the walls of each molding member that extend in a vertical plane for molding each of the axial ends of said T-beam, horizontally extending means bridging the space between the lower portions of such vertically extending walls for molding the bottom of said web section, a strut operatively connected at one end to each of said slab molding walls, means mov-ably securing the other ends of each of said struts to support means, said last-named means comprising movable toggle joints so that said struts may be moved into two positions, means for pivotally mounting said first and second molding members on said support means, means on said support means spaced from said toggle joints for limiting movement of said toggle joints in one direction to cause the weight of the concrete in said slab section to assist in retaining the mold members in operating arrangement, and means for moving the toggle joints in the opposite direction to pivot `said molding members apart to free the molded concrete T-beam.

`6. Apparatus for molding a concrete T-beam having a horizontal ilat slab section and a vertical web section comprising a first molding member and a second molding memfber, each molding member having -a wall for lmolding a respective side of said web section, the wall of one molding member extending in a vertical plane parallel to the plane in which the wall of the other molding member extends, each molding member having a wall for molding the adjacent underside `of said slab section including means `for molding the associated lateral edge of the slab, vertically extending means atlixed to the transverse ends of each molding member and extending across the space between the Walls of each molding member that extend in a vertical plane for molding each axial end of said Tebeam, means in juxtaposition to and between said molding members for molding the bottom of said web section, a strut operatively connected -at one end to each of said slab molding walls, means movably anchoring the other ends of each of said struts to support means, said last-named means including movable toggle joints so that said struts may be moved into two positions, said support means pivotally mounting said molding members below the Iforming surface of said web bottom forming means, means mounted on said support means and spaced from said toggle joints for limiting movement of each of said toggle joints toward said web in `a position wherein the associated strut is positioned so as to cause t-he weight of the concretein said slab section to assist in retaining the molding members in operating arrangement and in tight engagement with said web bottom forming means, -and means for moving the toggle joints away from said web to pivot said molding members apart and free the molded concrete Tebeams.

References Cited in the file of this patent UNITED STATES PATENTS 266,602 Blum Oct. 13, 1882 757,094 Coltrin Apr. 12, 1904 2,489,604 Woods Nov. 29, 1949 2,489,607 Alexander Nov. 29, 1949 2,582,161 Randall Jan. 8, 1952 2,596,052 Stockmar May 6, 1952 2,648,889 Youtz Aug. 18, 1953V FOREIGN PATENTS 115,747 Austria June 10, 1930 561,135 Great Britain May 5, 1944 700,947 Great Britain Dec. 16, 1953 1,173,303 France Oct. 27, 1958 

1. FOR USE IN MOLDING APPARATUS FOR A CONCRETE BEAM HAVING A HORIZONTAL FLAT SLAB SECTION AND A VERTICAL WEB SECTION, AN ARTICLE OF MANUFACTURE COMPRISING A PIVOTALLY MOUNTED MOLDING MEMBER HAVING A FIRST FORMING SURFACE FOR FORMING A SIDE OF SAID WEB SECTION AND A SECOND FORMING SURFACE EXTENDING LATERALLY FROM SAID FIRST FORMING SURFACE FOR FORMING AN ADJACENT UNDERSIDE OF SAID SLAB SECTION, MEANS ON SAID SECOND FORMING SURFACE TO RECEIVE A FORMING MEMBER FOR THE LATERAL SIDE OF SAID SLAB SECTION, A RIGID STRUT PIOVOTALLY CONNECTED AT ONE OF ITS ENDS TO SAID MOLDING MEMBER BENEATH SAID SLAB FORMING SURFACE, A LINK HAVING A PIVOTAL CONNECTION AT ONE OF ITS ENDS WITH THE OTHER END OF SAID STRUT TO FORM A MOVABLE TOGGLE JOINT. SUPPORT MEANS, MEANS SECURING THE OTHER END OF SAID LINK TO SAID SUPPORT MEANS SO THAT SAID STRUT AND SAID LINK ARE MOVABLE INTO AND OUT OF COAXIAL ALIGNMENT, MEANS PIVOTALLY MOUNTING THE MOLDING MEMBER ON SAID SUPPORT MEANS FOR MOVEMENT OF SAID FIRST FORMING SURFACE, MEANS MOUNTED ON SAID SUPPORT MEANS IN SPACED RELATION TO SAID OTHER END OF SAID LINK FOR LIMITING THE MOVEMENT OF SAID TOGGLE JOINT IN ONE DIRECTION AT A POSITION WHEREBY SAID STRUT AND SAID LINK ARE OUT OF COAXIAL ALIGNMENT TO CAUSE THE WEIGHT OF CONCRETE ON SAID SLAB FORMING SURFACE TO LOCK SAID STRUT AND LINK IN PLACE, AND MEANS FOR MOVING SAID TOGGLE JOINT IN A SECOND DIRECTION TO CAUSE SAID MOLDING MEMBER TO PIVOT AND BE RELEASED FROM A CONCRETE BEAM FORMED THEREON. 